Field of the Disclosure
The present invention relates to a substrate processing apparatus, and more particularly, to a substrate processing apparatus and method which facilitate to improve uniformity of thin film material and also facilitate to control quality of thin film by the use of plasma space and source gas distributing space separately provided from each other.
Discussion of the Related Art
Generally, in order to manufacture a solar cell, a semiconductor device and a flat panel display device, it is necessary to form a predetermined thin film layer, a thin film circuit pattern or an optical pattern on a surface of substrate. To this end, a semiconductor manufacturing process may be carried out, for example, a thin film deposition process of depositing a thin film of a predetermined material on a substrate, a photo process of selectively exposing the thin film by the use of photosensitive material, and an etching process of forming a pattern by selectively removing an exposed portion of the thin film. The semiconductor manufacturing process is performed inside a substrate processing apparatus designed to be suitable for optimal circumstances. Recently, a substrate processing apparatus using plasma is generally used to carry out a deposition or etching process.
This substrate processing apparatus using plasma may be a PECVD (Plasma Enhanced Chemical Vapor Deposition) apparatus for forming a thin film, and a plasma etching apparatus for etching and patterning the thin film.
FIG. 1 illustrates a substrate processing apparatus according to the related art.
Referring to FIG. 1, the substrate processing apparatus according to the related art may include a chamber 10, a plasma electrode 20, a susceptor 30, and a gas distributing means 40.
The chamber 10 provides a reaction space for substrate processing. In this case, a predetermined portion of a bottom surface of the chamber 10 is communicated with an exhaust port 12 for discharging gas from the reaction space.
The plasma electrode 20 is provided over the chamber 10 so as to seal the reaction space.
One side of the plasma electrode 20 is electrically connected with a RF (Radio Frequency) power source 24 through a matching member 22. The RF power source 24 generates RF power of 40 MHz, and supplies the generated RF power to the plasma electrode 20. Also, a central portion of the plasma electrode 20 is communicated with a gas supply pipe 26 supplying source gas for the substrate processing. The matching member 22 is connected between the plasma electrode 20 and the RF power source 24, to thereby match load impedance and source impedance of the RF power supplied from the RF power source 24 to the plasma electrode 20.
The susceptor 30 is provided inside the chamber 10, and the susceptor 30 supports a plurality of substrates (W) loaded from the external. The susceptor 30 corresponds to an opposite electrode in opposite to the plasma electrode 20, and the susceptor 30 is electrically grounded by an elevating axis 32 for elevating the susceptor 30.
The elevating axis 32 moves upward or downward by an elevating apparatus (not shown). In this case, the elevating axis 32 is surrounded by a bellows 34 for sealing the bottom surface of the chamber 10, whereby the elevating axis 32 together with the bellow 34 seals the bottom surface of the chamber 10.
The gas distributing means 40 is provided below the plasma electrode 20, wherein the gas distributing means 40 confronts the susceptor 30. In this case, a gas diffusion space 42 is formed between the gas distributing means 40 and the plasma electrode 20, wherein source gas supplied from the gas supply pipe 26 penetrating through the plasma electrode 20 is diffused in the gas diffusion space 42. The gas distributing means 40 uniformly distributes the source gas to the entire area of the reaction space through a plurality of gas distributing holes 44 being communicated with the gas diffusion space 42.
In case of the substrate processing apparatus according to the related art, after the substrate (W) is loaded onto the susceptor 30, the predetermined source gas is distributed to the reaction space of the chamber 10, and an electromagnetic field is formed in the reaction space by the RF power supplied to the plasma electrode 20, whereby plasma is formed on the substrate (W) by the electromagnetic field, thereby forming the predetermined thin film on the substrate (W).
However, in case of the substrate processing apparatus according to the related art, the space for distributing the source gas is the same as the space for forming the plasma. Thus, uniformity in the thin film material deposited on the substrate (W) depends on plasma density uniformity formed in the reaction space, which might cause difficulty in controlling quality of the thin film formed on the substrate (W).